/*
	Lightbox JS: Fullsize Image Overlays 
	by Lokesh Dhakar - http://www.huddletogether.com

	Modified heavily for AutoBase vehicle image display
*/


// Configuration

var lbMainImageHeight 		= 480;
var thumbCount 				= 0;
var currentThumbIndex		= 0;
var currentThumbSelected;


// getPageScroll()
// Returns array with x,y page scroll values.
function getPageScroll(){

	var yScroll;

	if (self.pageYOffset) {
		yScroll = self.pageYOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
		yScroll = document.documentElement.scrollTop;
	} else if (document.body) {// all other Explorers
		yScroll = document.body.scrollTop;
	}

	arrayPageScroll = new Array('',yScroll) 
	return arrayPageScroll;
}


// getPageSize()
// Returns array with page width, height and window width, height
function getPageSize(){
	
	var xScroll, yScroll;
	
	if (window.innerHeight && window.scrollMaxY) {	
		xScroll = document.body.scrollWidth;
		yScroll = window.innerHeight + window.scrollMaxY;
	} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
		xScroll = document.body.scrollWidth;
		yScroll = document.body.scrollHeight;
	} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
		xScroll = document.body.offsetWidth;
		yScroll = document.body.offsetHeight;
	}
	
	var windowWidth, windowHeight;
	if (self.innerHeight) {	// all except Explorer
		windowWidth = self.innerWidth;
		windowHeight = self.innerHeight;
	} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
		windowWidth = document.documentElement.clientWidth;
		windowHeight = document.documentElement.clientHeight;
	} else if (document.body) { // other Explorers
		windowWidth = document.body.clientWidth;
		windowHeight = document.body.clientHeight;
	}	
	
	// for small pages with total height less then height of the viewport
	if(yScroll < windowHeight){
		pageHeight = windowHeight;
	} else { 
		pageHeight = yScroll;
	}

	// for small pages with total width less then width of the viewport
	if(xScroll < windowWidth){	
		pageWidth = windowWidth;
	} else {
		pageWidth = xScroll;
	}


	arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
	return arrayPageSize;
}


// pause(numberMillis)
// Pauses code execution for specified time. Uses busy code, not good.
function pause(numberMillis) {
	var now = new Date();
	var exitTime = now.getTime() + numberMillis;
	while (true) {
		now = new Date();
		if (now.getTime() > exitTime)
			return;
	}
}


// getKey(key)
// Gets keycode and handles navigation keys.
function getKey(e){

	if (e == null) { // ie
		keycode = event.keyCode;
	} else { // mozilla
		keycode = e.which;
	}
	key = String.fromCharCode(keycode).toLowerCase();

	if(keycode == 27)
		{ hideLightbox(); }
	else if(keycode == 37)
		{ lightboxMovePrevious(); }
	else if(keycode == 39)
		{ lightboxMoveNext(); }
}


// listenKey()
function listenKey () 
{	
	document.onkeyup = getKey; 
}
	

// showLightbox()
// Preloads images. Pleaces new image in lightbox then centers and displays.
function showLightbox(objLink)
{
   
	// prep objects
	var objOverlay = document.getElementById('overlay');
	var objLightbox = document.getElementById('lightbox');
	var objLightboxHeader = document.getElementById('lightboxHeader');
	
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();

	// set height of Overlay to take up whole page and show
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	objOverlay.style.display = 'block';
	
	// center lightbox and make sure that the top and left values are not negative
	// and the image placed outside the viewport

	var lightboxWidth = parseInt(objLightbox.style.width);	
	var lightboxTop = arrayPageScroll[1] + ((arrayPageSize[3] - lbMainImageHeight) / 2);
	var lightboxLeft = ((arrayPageSize[2] - lightboxWidth ) / 2);

	objLightbox.style.top = (lightboxTop < 0) ? "0px" : lightboxTop + "px";
	objLightbox.style.left = (lightboxLeft < 0) ? "0px" : lightboxLeft + "px";
	
	// Add 2 pixels for correction of display in IE
	if (navigator.appVersion.indexOf("MSIE")!=-1){
		objLightboxHeader.style.width = parseInt(objLightboxHeader.style.width) + 2 + "px";	
	} 
	
	// A small pause between the image loading and displaying is required with IE,
	// this prevents the previous image displaying for a short burst causing flicker.
	if (navigator.appVersion.indexOf("MSIE")!=-1){
		pause(250);
	} 

	// Hide select boxes as they will 'peek' through the image in IE
	selects = document.getElementsByTagName("select");
       for (i = 0; i != selects.length; i++) {
               selects[i].style.visibility = "hidden";
       }
	   
	objLightbox.style.display = 'block';

	// After image is loaded, update the overlay height as the new image might have
	// increased the overall page height.
	arrayPageSize = getPageSize();
	objOverlay.style.height = (arrayPageSize[1] + 'px');
	
	// Check for 'x' keypress
	listenKey();
	

}


// hideLightbox()
function hideLightbox()
{
	// get objects

	objOverlay = document.getElementById('overlay');
	objLightbox = document.getElementById('lightbox');

	// hide lightbox and overlay
	objOverlay.style.display = 'none';
	objLightbox.style.display = 'none';

	// make select boxes visible
	selects = document.getElementsByTagName("select");
    for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "visible";
	}

	// disable keypress listener
	document.onkeyup = '';
}


// initLightbox()
// Function runs on window load, going through link tags looking for rel="lightbox".
// These links receive onclick events that enable the lightbox display for their targets.
// The function also inserts html markup at the top of the page which will be used as a
// container for the overlay pattern and the inline image.
function initLightbox()
{
	if (!document.getElementsByTagName){ return; }
	
	var anchors = document.getElementsByTagName("a");

	// loop through all anchor tags
	for (var i=0; i<anchors.length; i++){
		var anchor = anchors[i];

		if (anchor.getAttribute("href") && (anchor.getAttribute("rel") == "lightbox")){
			anchor.onclick = function () {setLightboxMainImage(this.getAttribute("id")-1); selectLightboxThumb(this.getAttribute("id")-1); showLightbox(this); return false;}
		}
	}

    setLightboxThumbsCount();
    
	var objBody = document.getElementsByTagName("body")[0];

	// create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
	var objOverlay = document.createElement("div");
	objOverlay.setAttribute('id','overlay');
	objOverlay.onclick = function () {hideLightbox(); return false;}
	objOverlay.style.display = 'none';
	objOverlay.style.position = 'absolute';
	objOverlay.style.top = '0';
	objOverlay.style.left = '0';
	objOverlay.style.zIndex = '90';
 	objOverlay.style.width = '100%';
	objBody.insertBefore(objOverlay, objBody.firstChild);
	
	var arrayPageSize = getPageSize();
	var arrayPageScroll = getPageScroll();

	// create lightbox div, same note about styles as above
	var objLightbox = document.getElementById('lightbox');
	var objLightboxHeader = document.getElementById('lightboxHeader');
	//lightboxHeader
	
	objLightbox.style.display = 'none';
	objLightbox.style.position = 'absolute';
	objLightbox.style.zIndex = '100';	

	if (imageColumnCount == 1)
	{
	    objLightbox.style.width = '752px';
	    objLightboxHeader.style.width = '752px';
	}
	else if (imageColumnCount == 2)
	{
	    objLightbox.style.width = '830px';
	    objLightboxHeader.style.width = '830px';
	}	
	else if (imageColumnCount == 3)
	{
	    objLightbox.style.width = '920px';
	    objLightboxHeader.style.width = '920px';
	}
	objBody.insertBefore(objLightbox, objOverlay.nextSibling);
	
	// create link
	var objLink = document.createElement("a");
	objLink.setAttribute('href','#');
	objLink.setAttribute('title','Click to close');
	objLink.onclick = function () {hideLightbox(); return false;}
	objLightbox.appendChild(objLink);
	
	setAllLightboxThumbsClass('lightboxThumb');
}


function lightboxMovePrevious()
{
	var currIndex = currentThumbIndex;	
	if(currIndex > 0)
	{
		selectLightboxThumb(currIndex - 1);
		setLightboxMainImage(currIndex - 1);
	}
}

function lightboxMoveNext()
{
	var currIndex = currentThumbIndex;
	if(currIndex < thumbCount-1)
	{
		selectLightboxThumb(currIndex + 1);
		setLightboxMainImage(currIndex + 1);
	}
}


function setLightboxMainImage(imageIndex)
{
	imageIndex = parseInt(imageIndex);
	document.images.lightboxMainImage.src = picArray[imageIndex];
	
	info = document.getElementById("lightboxNavInfo");
	info.innerHTML = "Image " + eval(imageIndex + 1) + " of " + thumbCount;
	
	currentThumbIndex = imageIndex;
}


function setAllLightboxThumbsClass(newClassName)
{
    for (i = 0; i < thumbCount-1; i++) 
	{
	 	document.getElementById("lightboxThumb" + i).className = newClassName;
    }
}


function selectLightboxThumb(indx)
{

	var newSelectedThumb = document.getElementById("lightboxThumb" + indx);
	newSelectedThumb.className = 'lightboxThumbSelected';

	if((currentThumbSelected != null) && (currentThumbSelected != newSelectedThumb))
		currentThumbSelected.className = 'lightboxThumb';
		
	currentThumbSelected = newSelectedThumb;
	currentThumbIndex = indx;

}


function setLightboxThumbsCount()
{
 	allImgs = document.getElementsByTagName("img");
    for (i = 0; i != allImgs.length; i++) 
	{
	 	if (allImgs[i].name.substring(0, 13) == "lightboxThumb")
             thumbCount++;
     }		 
}


// addLoadEvent()
// Adds event to window.onload without overwriting currently assigned onload functions.
// Function found at Simon Willison's weblog - http://simon.incutio.com/
function addLoadEvent(func)
{	

	var oldonload = window.onload;
	if (typeof window.onload != 'function'){
    	window.onload = func;
	} else {
		window.onload = function(){
		oldonload();
		func();
		}
	}
}

addLoadEvent(initLightbox);	// run initLightbox onLoad